1. Field of The Invention
The invention relates to circulators, and particularly to the fiber optic circulator with simple structures thereof.
2. The Related Art
An fiber optic circulator is designed to provide a non-reciprocal multi-port optical device which allows the forward light beam and the backward light beam to travel therethrough in different paths. Therefore, in a three ports fiber optic circulator the light beam coupled into the first port will propagate out from the second port and the light beam coupled into the second port will propagate out from the third port. Anyhow, the traditional circulator has complicated structures and parts. The theory and application of the circulator can be referred to the publication of "Optical Waves in Crystals" having the authors of Amnon Yariv and Pochi Yeh, and U.S. Pat. Nos. 5,574,596, 5,581,640, 5,631,771, 5,661,829, 5,689,593 and 5,734,762.
Therefore, an object of the invention is to provide an inexpensive device with simplified structures thereof for achieving the same function.